As one legal historian wrote, Justinian consciously looked back to the golden age of Roman law and aimed to restore it to the peak it had reached three centuries before.Western Europe, meanwhile, slowly slipped into the Dark Ages, and it was not until the 11th century that scholars in the University of Bologna rediscovered the texts and used them to interpret their own laws.

Civil law codifications based closely on Roman law, alongside some influences from religious laws such as Canon law and Islamic law, continued to spread throughout Europe until the Enlightenment; then, in the 19th century, both France, with the Code Civil, and Germany, with the Bürgerliches Gesetzbuch, modernised their legal codes.

European Union law is the first and thus far only example of a supranational legal framework. However, given increasing global economic integration, many regional agreements—especially the Union of South American Nations—are on track to follow the same model. Sovereign nations have pooled their authority through a system of courts and political institutions. They have the ability to enforce legal norms against and for member states and citizens, in a way that public international law does not. As the European Court of Justice, European Union law constitutes a new legal order of international law for the mutual social and economic benefit of the member states.Civil law is the legal system used in most countries around the world today.